72039442 has 4 divisors (see below), whose sum is σ = 108059166. Its totient is φ = 36019720.

The previous prime is 72039439. The next prime is 72039463. The reversal of 72039442 is 24493027.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 70241161 + 1798281 = 8381^2 + 1341^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18009859 + ... + 18009862.

Almost surely, 2^72039442 is an apocalyptic number.

72039442 is a deficient number, since it is larger than the sum of its proper divisors (36019724).

72039442 is a wasteful number, since it uses less digits than its factorization.

72039442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36019723.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 72039442 is about 8487.6051981699. The cubic root of 72039442 is about 416.0927161748.

The spelling of 72039442 in words is "seventy-two million, thirty-nine thousand, four hundred forty-two".